After reading this question, I understand that you running two sequences config_seq and data_seq on driver. config_seq doesnt need rsp and data_seq requires rsp from dut.
So if using same driver how does the config_seq handles the rsp, since it does not have mechanism to handle rsp
Example code
//driver run task
seq_item_port.get_next_item(req);
drive_dut(req);
seq_item_port.item_done(rsp);
//config_seq
start_item(req);
req.randomize();
finish_item(); //how does rsp is handled here? rsp fifo might overflow since use the rsp here.
//data_seq
start_item(req);
req.randomize();
finish_item();
get_response(rsp); //rsp handled here